Horn was late to the pre-fight weigh-in because of Friday night traffic in Brisbane but made up for lost time with a swift first-round finish.

The 43-year-old Mundine, who twice held the WBA super-middleweight title, looked sluggish from the start. He took several heavy blows from the faster, stronger Horn before being floored with a left-hook which slipped past his right glove.

Mundine later said his “time’s up” as a boxer, ending an 18-year professional career which followed his successful career in rugby league.

“Jeff proved tonight he’s the better man,” Mundine said. “That’s the next generation man. I was ready. I was prepared well. It’s just boxing, you get caught sometimes.”

The bout took on increased significance for Horn, the former WBO welterweight champion who suffered his first professional loss to American Terence Crawford in June.

“I feel really, really strong at this weight,” Horn said. “I was expecting a hard fight. I’m happy to get it over and done quickly.”

The non-title fight was a catchweight at 71 kilograms (156 pounds). Catchweight refers to a weight division which falls outside traditional weight classes but which both boxers agree on before the fight

Horn, 30, came into the fight with 18 wins in 19 fights, 12 by knockout. Mundine, a 43-year-old former rugby league player, had fought 56 times with 48 wins, 28 by knockout, and eight losses.

Horn’s biggest and most controversial fight came on July 2, 2017 in the same Suncorp Stadium when he beat Manny Pacquiao for the WBO welterweight title in a unanimous decision that many boxing commentators said should have been awarded to Pacquiao.

Horn lost that title to Terence Crawford in Las Vegas in June. Before the fight against Mundine, Horn talked about trying to get a rematch with Crawford in Australia.